rvm in vbox for making it possible to use different versions of ruby/rails.

From cygwin, start vbox using "vagrant up". Do "vagrant ssh" to get regular shell interface to use Guest vbox.

Use a folder (referred as WIN_HOST_PROJ_DIR here) on Host Windows machine that'll keep the project code/data which is built using Guest Virtual Box (such as Ububtu). It also contains Vagrantfile for the project and "id" file for the vbox being used.